Physics Midterm 1

unit conversions

giga (G)

mega (M)

kilo (k)

centi c

milli (m)

10^9

10^6 (think million)

10^3 (think money k = 1000)

10^-2

10^-3

what is displacement

the change in the particles position over a time interval

• dont are about the path taken only change in point

• also a vector quantity (has magnitude and dir)

what is the magnitude of a vector

its the numerical amount of the vector without regard to its direction; it is always a positive quantity.

what are the x and y components of the displacement vector

what does the sign mean for the displacement vector

The sign of a displacement vector indicates the direction of the displacement in relation to a chosen coordinate system

what does the sign mean for the velocity vector

The sign of a velocity vector indicates the direction of motion in relation to a chosen coordinate system

what does the sign of the acceleration mean for the acceleration vector

The sign of an acceleration vector indicates the direction of acceleration in relation to a chosen coordinate system.

how to find the magnitude of a vector from its x and y components

use the pythagorean theorum and then take the absolute value of the number

how does vector multiplication by a scalar work component wise

When a vector is multiplied by a scalar, each component of the vector is multiplied by that scalar, effectively scaling the vector's magnitude while maintaining its direction.

if its a negative number the vector changes direction

what is the direction and magnitude of the velocity vector

the direction is the direction of the motion and the magnitude is the speed at which the object is moving

what is the units for velocity

m/s

how does vector addition work component wise

Vector addition involves adding corresponding components of two or more vectors. The result is a new vector where each component is the sum of the respective components from the original vectors.

what is the magnitude and the direction of the acceleration vector

the magnitude is the rate of change of the velocity or the derivative of it and the 2nd derivative of the positon and the direction is the direction in which velocity changes.

what does the acceleration vector tell us

how the velocoty of an object is changing at any instant in time

how do you calculate the x and y comp of acceleration

slope of tangent line to vx vs t graph and vy vs t graph

so positive velocity slope means pos accel and neg velocity slope means neg accel

what is the turning point

an object with opposite velocity and acceleration will eventually stop and change direction, this is the turning point

and the velocity if 0 at this point

what does the acceleration tell us about the position vs time graph

its concavity, pos accel is concave up and neg is concave down

what are the units for acceleration

m/s²

over a given amount of seconds how does the m/s change

how to calculate average acceleration

Average acceleration is calculated by dividing the change in velocity by the time interval over which the change occurs.

how do you think about acceleration in relation to the velocity and if the object is speeding up or down

think of it as pulling or pushing on the velcity, therefore if the acceleration is in the same direction as velocity, the object is speeding up; if opposite, it is slowing down.

how to find vector components when given their magnitude and angle in the pos x dir

how to find vector components when given their magnitude and angle in the neg x dir

what is cos, sin and tan

cosine is the adjacent side over the hypotenuse, sine is the opposite side over the hypotenuse, and tangent is the opposite side over the adjacent side.

how do you add the two magnitudes of vectors

decomppose the vectors add component wise and then apply pythag theorum to get magnitude of new vector

how do you find the angle when given x and y components

take the inverse tangent of y comp / x comp

what do you do to the angle output if you want to find the angle of a vector in the neg x direction (2/3 quad)

add 180 degrees to the angle output.

if velocity is constant what is the acceleration

0

what are the x and y components of the velocity vector

the derivative of the position or the slope of the tangent line

what does a steeper slope mean for a position graph

It indicates a greater velocity, meaning the object is moving faster. A steeper slope represents a rapid change in position over time.

what is uniform motion

Motion at a constant speed in a straight line, where the position of an object changes uniformly over time.

how do you find the x component of uniform motion

since the velocity of uniform motion is constant (straight slope) then the x comp is equal to the

what is the position of an object at any time in uniform motion

how to calculate displacement in uniform motion

make sure to only calculate the area of time being asked

what does it mean if the velocity goes below 0

It indicates that the object is moving in the opposite direction to the reference point, often referred to as negative velocity.

tips for solving kinematics problems

what is constant acceleration motion

an object under the influence of gravity will move in constant acceleration motion down

what are the eq for constant acceleration

velocity comp:

position at time of an object moving with const accel

what is the equation without time (for when time isnt needed)

when you have constant acceleration and velocity and accel start in opposite directions hwo long does it take to get to max position and back to inital position

it take double the max position to get back to initial position from start

what is free fall motion

vertical motion under the influence of gravity alone

it is one dimentional constant acceleration motion

what is the dir and magnitude of the gravitational acceleration

constant with a mag of 9.8 and is pointing down

g is always positive because it is the magnitude of the acceleration

what is the y and x comp of accel in free fall motion

since our y axis is pointing up it is -g, the x comp is 0 because there is no change in the x direction

what are the equations for free fall motion

what is the quadratic formula

what are important points about free fall motion

at any given height an object will have the same speed moving down as it is up

dont mistake v=0 at the ground (think its the instant before contact)

what is projectile motion

a two dimensional motion where we have to account for both horizontal and vertical motion of a particle

what are the coordinate axes in projectile motion

what are the 2 independent but simultaneas motions in projectile motion

horizontal: since ax is 0 the motion in the x direction is uniform motion

vertical: in the y dir we have free fall motion, ay = -g

since the two motions occur simultaneously we will often use time to relate them (solve for time from one then plugging into the other)

what are the standard equations for projectile motion

how to find x and y comp of projectile motion

what are the equations for projectile motion with the x and y comp as angles

how does the acceleration of projectile motion cause its trajectory

what is uniform circular motion

motion in a circle at constant speed

how is UCM periodic motion

it repeats at regular time intervals

what is the period (T) of UCM

the time it takes for the motion to repeat

what is each full circle in UCM

revolution or cycle

what is the frequency of UCM

the number of revolutions per unit time

• frequenccy measures the rate of repetition: higher frequency means the motion repeats more often

how is frequency related to the period (eq)

what are units of frequency in UCM

what is the arc length in ucm

The distance traveled by an object moving along a circular path, measured in radians.

what is the velocity in UCM

how does the accel relate to the path of UCM and what is centripetal acceleration (ac)

since velo is const changing direction the accel is changing too. Therefore always pointing towards the middle and pulling the velocity around the circle.

what is eq for Ac